Method and device for establishing electrolyte concentration of flow battery and flow battery

Abstract

The embodiment of the invention discloses a method and a device for establishing electrolyte concentration of a flow battery and the flow battery. The method comprises the following steps: acquiring operating parameters of a target flow battery during load changing; querying a rotating speed characteristic diagram of the circulating pump based on the operation parameters, and determining a variable load required rotating speed of the target flow battery; determining rotation speed adjusting duration based on the variable load demand rotation speed; determining the change duration of the variable load current based on the rotation speed adjustment duration; and the establishment rate of the electrolyte concentration of the target flow battery after load change is constrained based on the change duration, and the output power of the load is ensured. According to the method, the rotating speed characteristic diagram of the circulating pump is inquired based on the operating parameters of the target flow battery during load changing, the change duration of the load changing current is determined according to the load changing requirement of the circulating pump, then the establishment rate of the electrolyte concentration is restrained, and the technical problems that under the dynamic working condition, the electrolyte flow change is not timely followed, and side reactions are likely to occur are solved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the technical field of flow batteries, and in particular, to a method and device for establishing the electrolyte concentration of a flow battery and a flow battery. Background Art

[0002] Currently, the electrolyte flow control of flow batteries is mainly based on the requirements of steady-state operating conditions. The dynamic operating conditions in load-following scenarios have different requirements for flow rate. Since the electrochemical reaction rate on the electrode surface is fast, but the mass transfer inside the porous electrode is relatively slow, in dynamic operating conditions, it is necessary to adjust the follow-up strategy of the electrolyte flow rate to promptly establish the concentration of interfacial reactants and avoid side reactions. Summary of the Invention

[0003] Embodiments of the present invention provide a method and device for establishing the electrolyte concentration of a flow battery and a flow battery, which solve the technical problem that the change of the electrolyte flow rate in dynamic operating conditions follows untimely and side reactions are likely to occur.

[0004] Embodiments of the present invention provide a method for establishing the electrolyte concentration of a flow battery, and the method includes:

[0005] Obtain the operating parameters of the target flow battery during variable load;

[0006] Query the rotational speed characteristic diagram of the circulation pump based on the operating parameters to determine the variable load required rotational speed of the target flow battery;

[0007] Determine the rotational speed adjustment duration based on the variable load required rotational speed;

[0008] Determine the change duration of the variable load current based on the rotational speed adjustment duration;

[0009] Constrain the establishment rate of the electrolyte concentration of the target flow battery after variable load based on the change duration to ensure the output power to the load.

[0010] Further, before constraining the establishment rate of the electrolyte concentration of the target flow battery after variable load based on the change duration, the method further includes:

[0011] Obtain the single-cell voltage of the target flow battery during variable load;

[0012] Determine the correction amount of the change duration of the variable load current based on the single-cell voltage;

[0013] Correct the change duration based on the correction amount of the change duration.

[0014] Further, determining the correction amount of the change duration of the variable load current based on the single-cell voltage includes:

[0015] Subtract the single-cell voltage from the preset standard single-cell voltage to obtain a target voltage difference;

[0016] Based on the target voltage difference and a preset difference threshold, determine whether it is necessary to correct the change duration of the variable load current;

[0017] If the target voltage difference is less than the preset difference threshold and the continuous duration is greater than or equal to a preset duration threshold, the change duration correction amount is 0;

[0018] If the target voltage difference is greater than or equal to the preset difference threshold, determine the change duration correction amount based on the target voltage difference.

[0019] Further, determining the change duration correction amount based on the target voltage difference includes:

[0020] Calculate the adjustment amount of the variable load current based on the target voltage difference and the single-cell internal resistance of the target flow battery;

[0021] Determine the change duration correction amount based on the adjustment amount of the variable load current.

[0022] Further, obtaining the operating parameters of the target flow battery during variable load includes:

[0023] Obtain the current capacity of the target flow battery, the current temperature of the target flow battery, the current circulation pump speed of the target flow battery, and the variable load current of the target flow battery.

[0024] Further, querying the circulation pump speed characteristic diagram based on the operating parameters to determine the variable load required speed of the target flow battery includes:

[0025] Determine the corresponding flow resistance curve based on the current capacity or the current temperature;

[0026] Determine the flow rate demand corresponding to the load after variable load based on the variable load current;

[0027] Based on the flow resistance curve and the flow rate demand, use the circulation pump speed characteristic diagram to determine the variable load required speed of the target flow battery.

[0028] Further, determining the speed adjustment duration based on the variable load required speed includes:

[0029] Query the variable load rate curve diagram of the corresponding circulation pump based on the current circulation pump speed and the variable load required speed to determine the speed adjustment duration.

[0030] An embodiment of the present invention also provides an electrolyte concentration establishment device for a flow battery, and the device includes:

[0031] A parameter acquisition unit for acquiring the operating parameters of a target flow battery during variable load;

[0032] A rotational speed determination unit for querying a rotational speed characteristic diagram of a circulation pump based on the operating parameters and determining the variable load required rotational speed of the target flow battery;

[0033] A first time determination unit for determining a rotational speed adjustment duration based on the variable load required rotational speed;

[0034] A second time determination unit for determining the change duration of the variable load current based on the rotational speed adjustment duration;

[0035] A concentration establishment constraint unit for constraining the establishment rate of the electrolyte concentration of the target flow battery after variable load based on the change duration to ensure the output power to the load.

[0036] Further, before constraining the establishment rate of the electrolyte concentration of the target flow battery after variable load based on the change duration, the device further includes:

[0037] A voltage acquisition unit for acquiring the single cell voltage of the target flow battery during variable load;

[0038] A correction amount determination unit for determining a change duration correction amount of the variable load current based on the single cell voltage;

[0039] A duration correction unit for correcting the change duration based on the change duration correction amount.

[0040] An embodiment of the present invention further provides a flow battery, and the flow battery executes the electrolyte concentration establishment method of the flow battery described in any of the above embodiments.

[0041] An embodiment of the present invention discloses an electrolyte concentration establishment method, device and flow battery for a flow battery. The method includes: acquiring the operating parameters of a target flow battery during variable load; querying a rotational speed characteristic diagram of a circulation pump based on the operating parameters to determine the variable load required rotational speed of the target flow battery; determining a rotational speed adjustment duration based on the variable load required rotational speed; determining the change duration of the variable load current based on the rotational speed adjustment duration; constraining the establishment rate of the electrolyte concentration of the target flow battery after variable load based on the change duration to ensure the output power to the load. This application queries the rotational speed characteristic diagram of the circulation pump based on the operating parameters of the target flow battery during variable load, determines the change duration of the variable load current through the variable load requirements of the circulation pump, and further constrains the establishment rate of the electrolyte concentration, solving the technical problem that the change of the electrolyte flow rate does not follow in time under dynamic working conditions and side reactions are likely to occur, achieving the technical effect of maximizing the load response rate of the flow battery while avoiding side reactions and extending the service life of the flow battery. Description of the Drawings

[0042] Figure 1 is a flowchart of a method for establishing the electrolyte concentration of a flow battery provided by an embodiment of the present invention;

[0043] Figure 2 is a characteristic diagram of the rotational speed of a circulation pump provided by an embodiment of the present invention;

[0044] Figure 3 is a variable load rate curve diagram provided by an embodiment of the present invention;

[0045] Figure 4 is a flowchart of another method for establishing the electrolyte concentration of a flow battery provided by an embodiment of the present invention;

[0046] Figure 5 is a structural diagram of a device for establishing the electrolyte concentration of a flow battery provided by an embodiment of the present invention. Detailed implementation manners

[0047] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the sake of description, only parts related to the present invention are shown in the drawings rather than all structures.

[0048] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the drawings are used to distinguish different objects, rather than to limit a specific order. Each of the following embodiments of the present invention can be executed independently, and the embodiments can also be combined with each other for execution. The embodiments of the present invention do not make specific limitations in this regard.

[0049] Figure 1 is a flowchart of a method for establishing the electrolyte concentration of a flow battery provided by an embodiment of the present invention.

[0050] As Figure 1 shown, the method for establishing the electrolyte concentration of the flow battery specifically includes the following steps:

[0051] S101, obtain the operating parameters of the target flow battery during variable load.

[0052] Among them, the operating parameters during variable load at least include the current capacity (State of Charge, SOC), the current temperature, the current circulating pump speed, and the variable load current. Specifically, the current temperature, the current circulating pump speed, and the variable load current can be obtained through sensors. The current capacity of the target flow battery is calculated by measuring the open circuit voltage (Open circuit voltage, OCV) of the target flow battery and according to the OCV-SOC fitting curve. The sensors at least include a current sensor, a temperature sensor, and a speed sensor.

[0053] S102. Query the circulating pump speed characteristic diagram based on the operating parameters, and determine the variable load required speed of the target flow battery.

[0054] Figure 2 is the circulating pump speed characteristic diagram provided by the embodiment of the present invention. Refer to Figure 2 , Figure 2 In the figure, the black dotted lines are the circulating pump characteristic curves corresponding to different speeds, and the red solid line is the flow resistance of the electrode reactants corresponding to different capacities or different temperatures of the target flow battery, that is, the flow resistance curve.

[0055] In the embodiment of the present invention, first, the flow resistance curve under the corresponding working condition is determined based on the current capacity or the current temperature in the operating parameters, then the flow rate demand corresponding to the load after variable load is determined based on the variable load current, and finally, the circulating pump characteristic curve is queried based on the flow resistance curve and the flow rate demand, and the speed corresponding to the intersection point is the variable load required speed of the target flow battery.

[0056] Exemplarily, refer to Figure 2 , curve a0 is the flow resistance curve under the corresponding working condition determined based on the current capacity or the current temperature. Point A is the intersection point of the current circulating pump speed n1 before variable load corresponding to the current capacity or the current temperature and the flow resistance curve, and the corresponding flow rate demand is Q1. Point B is the point on the flow resistance curve a0 corresponding to the flow rate demand Q2 of the electrolyte required for the corresponding load after variable load determined based on the variable load current. Then the speed corresponding to point B is the variable load required speed n2.

[0057] S103. Determine the speed adjustment duration based on the variable load required speed.

[0058] Figure 3 is the variable load rate curve diagram provided by the embodiment of the present invention.

[0059] Specifically, after obtaining the variable load required speed n2, query the variable load rate curve diagram as shown in Figure 3 . Based on the current circulating pump speed n1 and the variable load required speed n2, the corresponding variable load rate can be obtained, and further, the speed adjustment duration t required to change from the current circulating pump speed n1 to the variable load required speed n2 can be obtained.

[0060] S104. Determine the change duration of the variable-load current based on the rotation speed adjustment duration.

[0061] Specifically, the change duration of the variable-load current is determined according to the rotation speed adjustment duration t. Generally, the change duration of the variable-load current can be selected to be equal to the rotation speed adjustment duration t, or the ratio between the change duration of the variable-load current and the rotation speed adjustment duration t can be associated according to the type, characteristics, etc. of the flow battery, and no specific limitation is made here.

[0062] S105. Constrain the establishment rate of the electrolyte concentration of the target flow battery after variable load based on the change duration to ensure the output power to the load.

[0063] Specifically, since the electrolyte concentration is related to the SOC of the target flow battery, and the variable-load current represents the demand for the electrolyte concentration, after obtaining the change duration of the variable-load current, this change duration is the response duration of the change in the electrolyte flow rate during variable load, thereby realizing the constraint on the establishment rate of the electrolyte concentration of the target flow battery, effectively improving the load response speed of the target flow battery, and ensuring the output power to the load after variable load.

[0064] This application queries the rotation speed characteristic diagram of the circulation pump based on the operating parameters of the target flow battery during variable load, determines the change duration of the variable-load current through the variable-load demand of the circulation pump, and then constrains the establishment rate of the electrolyte concentration, solving the technical problem that the change in the electrolyte flow rate does not follow in time under dynamic working conditions and side reactions are likely to occur, achieving the technical effect of maximizing the load response rate of the flow battery while avoiding side reactions and extending the service life of the flow battery.

[0065] Based on the above technical solutions, Figure 4 is a flowchart of another method for establishing the electrolyte concentration of a flow battery provided by an embodiment of the present invention. As Figure 4 shown, before S105 constrains the establishment rate of the electrolyte concentration of the target flow battery after variable load based on the change duration, the method further includes:

[0066] S401. Obtain the single-cell voltage of the target flow battery during variable load.

[0067] Specifically, a target flow battery may be composed of a single battery cell or a stack composed of multiple battery cells. The single-cell voltage refers to the voltage of a single battery cell in the flow battery.

[0068] S402. Determine the correction amount of the change duration of the variable-load current based on the single-cell voltage.

[0069] Specifically, during the variable load process, the single-cell voltage of the target flow battery is monitored in real time, and the variation duration correction amount of the variable load current can be determined according to the deviation degree between the single-cell voltage and the standard single-cell voltage. It should be noted that when the target flow battery is in the amplification state, the battery voltage is a minimum voltage lower than the standard single-cell voltage. When the target flow battery is in the charging process, the battery voltage is a maximum voltage higher than the standard single-cell voltage. The difference between the battery voltage and the standard single-cell voltage is used to characterize the degree of deviation of the battery voltage from the standard single-cell voltage.

[0070] S403. Correct the variation duration based on the variation duration correction amount.

[0071] Specifically, after obtaining the variation duration correction amount, the variation duration of the variable load current is corrected to obtain a more accurate limit of the variation duration of the variable load current, thereby achieving a more accurate constraint on the establishment rate of the electrolyte concentration.

[0072] Based on the above technical solutions, S402 specifically includes:

[0073] Subtract the single-cell voltage from the preset standard single-cell voltage to obtain a target voltage difference; determine whether it is necessary to correct the variation duration of the variable load current based on the target voltage difference and the preset difference threshold; if the target voltage difference is less than the preset difference threshold and the continuous duration is greater than or equal to the preset duration threshold, the variation duration correction amount is 0; if the target voltage difference is greater than or equal to the preset difference threshold, determine the variation duration correction amount based on the target voltage difference.

[0074] Specifically, after obtaining the single-cell voltage V1, subtract the single-cell voltage V1 from the standard single-cell voltage V0 to obtain a target voltage difference (V0 - V1); compare the target voltage difference (V0 - V1) with the preset difference threshold m. If V0 - V1 < m and the continuous duration is greater than or equal to the preset duration threshold, there is no need to correct the variation duration, and the correction amount of the variation duration is 0. Among them, the preset duration threshold can be set to 5 s according to needs; if V0 - V1 ≥ m, take the current variable load current as the maximum working current, and calculate the correction amount of the variable load current based on the target voltage difference, and then obtain the correction amount of the variation duration.

[0075] Optionally, determining the variation duration correction amount based on the target voltage difference includes:

[0076] Calculate the adjustment amount of the variable load current based on the target voltage difference and the internal resistance of the single cell of the target flow battery; determine the variation duration correction amount based on the adjustment amount of the variable load current.

[0077] Specifically, the regulation amount of the variable load current △I = (V0 - V1) / R, where R is the internal resistance of a single cell of the target flow battery. After obtaining the regulation amount of the variable load current, the variable load current is regulated based on the regulation amount of the variable load current, and then the correction amount of the change duration of the variable load current is calculated.

[0078] Optionally, in S101, obtaining the operating parameters of the target flow battery during variable load includes:

[0079] Obtaining the current capacity of the target flow battery, the current temperature of the target flow battery, the current rotational speed of the target flow battery's circulation pump, and the variable load current of the target flow battery.

[0080] Specifically, the current temperature, the current rotational speed of the circulation pump, and the variable load current can be obtained through sensors, and the current capacity of the target flow battery is calculated by testing the open-circuit voltage of the target flow battery and according to the OCV-SOC fitting curve.

[0081] Optionally, in S102, querying the circulation pump rotational speed characteristic diagram based on the operating parameters to determine the variable load required rotational speed of the target flow battery includes:

[0082] Determining the corresponding flow resistance curve based on the current capacity or the current temperature; determining the flow rate demand corresponding to the load after variable load based on the variable load current; and determining the variable load required rotational speed of the target flow battery by using the circulation pump rotational speed characteristic diagram based on the flow resistance curve and the flow rate demand.

[0083] Specifically, Figure 2 The red implementation in represents any one of the flow resistance curves determined by capacity and the flow resistance curve determined by temperature. First, determine the flow resistance curve under the corresponding working condition based on the current capacity or the current temperature in the operating parameters, then determine the flow rate demand corresponding to the load after variable load based on the variable load current, and finally query the circulation pump characteristic curve based on the flow resistance curve and the flow rate demand. The rotational speed corresponding to the intersection point is the variable load required rotational speed of the target flow battery.

[0084] Optionally, in S103, determining the rotational speed regulation duration based on the variable load required rotational speed includes:

[0085] Querying the variable load rate curve diagram of the corresponding circulation pump based on the current rotational speed of the circulation pump and the variable load required rotational speed to determine the rotational speed regulation duration.

[0086] Specifically, after obtaining the variable load required rotational speed n2, query the variable load rate curve diagram as shown in Figure 3 . Based on the current rotational speed n1 of the circulation pump and the variable load required rotational speed n2, the corresponding variable load rate can be obtained, and then the rotational speed regulation duration t required to change from the current rotational speed n1 of the circulation pump to the variable load required rotational speed n2 can be obtained.

[0087] Figure 5It is a structural diagram of an electrolyte concentration establishing device for a flow battery provided by an embodiment of the present invention.

[0088] As Figure 5 shown, the electrolyte concentration establishing device of the flow battery includes:

[0089] A parameter acquisition unit 51, configured to acquire the operating parameters of the target flow battery during variable load;

[0090] A rotation speed determination unit 52, configured to query the rotation speed characteristic diagram of the circulation pump based on the operating parameters and determine the variable load required rotation speed of the target flow battery;

[0091] A first time determination unit 53, configured to determine the rotation speed adjustment duration based on the variable load required rotation speed;

[0092] A second time determination unit 54, configured to determine the change duration of the variable load current based on the rotation speed adjustment duration;

[0093] A concentration establishment constraint unit 55, configured to constrain the establishment rate of the electrolyte concentration of the target flow battery after variable load based on the change duration to ensure the output power to the load.

[0094] Optionally, before the concentration establishment constraint unit 55 constrains the establishment rate of the electrolyte concentration of the target flow battery after variable load, the device further includes:

[0095] A voltage acquisition unit, configured to acquire the single cell voltage of the target flow battery during variable load;

[0096] A correction amount determination unit, configured to determine the change duration correction amount of the variable load current based on the single cell voltage;

[0097] A duration correction unit, configured to correct the change duration based on the change duration correction amount.

[0098] Optionally, the correction amount determination unit is specifically configured to:

[0099] Subtract the single cell voltage from the preset standard single cell voltage to obtain the target voltage difference; determine whether it is necessary to correct the change duration of the variable load current based on the target voltage difference and the preset difference threshold; if the target voltage difference is less than the preset difference threshold and the continuous duration is greater than or equal to the preset duration threshold, the change duration correction amount is 0; if the target voltage difference is greater than or equal to the preset difference threshold, determine the change duration correction amount based on the target voltage difference.

[0100] Optionally, the correction amount determination unit is further configured to: calculate the adjustment amount of the variable load current based on the target voltage difference and the internal resistance of the single cell of the target flow battery; determine the change duration correction amount based on the adjustment amount of the variable load current.

[0101] Optionally, the parameter acquisition unit 51 is specifically configured to:

[0102] Obtain the current capacity of the target flow battery, the current temperature of the target flow battery, the current rotation speed of the circulation pump of the target flow battery, and the variable load current of the target flow battery.

[0103] Optionally, the rotation speed determination unit 52 is specifically configured to:

[0104] Determine the corresponding flow resistance curve based on the current capacity or the current temperature;

[0105] Determine the flow rate requirement corresponding to the load after variable load based on the variable load current;

[0106] Based on the flow resistance curve and the flow rate requirement, use the circulation pump rotation speed characteristic diagram to determine the variable load required rotation speed of the target flow battery.

[0107] Optionally, the first time determination unit 53 is specifically configured to:

[0108] Query the variable load rate curve diagram of the corresponding circulation pump based on the current rotation speed of the circulation pump and the variable load required rotation speed, and determine the rotation speed adjustment duration.

[0109] The electrolyte concentration establishment device of the flow battery provided by the embodiment of the present invention has the same technical features as the electrolyte concentration establishment method of the flow battery provided by the above embodiment, so it can also solve the same technical problems and achieve the same technical effects.

[0110] The embodiment of the present invention also provides a flow battery, and this flow battery executes the electrolyte concentration establishment method of the flow battery in any of the above embodiments.

[0111] The flow battery provided by the embodiment of the present invention executes the electrolyte concentration establishment method of the flow battery in the above embodiment. Therefore, the flow battery provided by the embodiment of the present invention also has the beneficial effects described in the above embodiment, which will not be elaborated here.

[0112] In the description of the embodiments of the present invention, unless otherwise clearly defined and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0113] Finally, it should be noted that the above are only the preferred embodiments of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for establishing electrolyte concentration of a flow battery, characterized in that: The method comprises: Obtaining the operating parameters of the target flow battery under variable load; Based on the operating parameters, query the circulation pump speed characteristic diagram to determine the variable load required speed of the target liquid flow battery; Determining a speed adjustment duration based on the variable load demand speed; Determining a change duration of the variable load current based on the speed adjustment duration; The establishment rate of the electrolyte concentration of the target flow battery after the load change is constrained based on the change time length, thereby ensuring the output power to the load.

2. The method for establishing electrolyte concentration of a flow battery according to claim 1, characterized in that: Before constraining the establishment rate of the electrolyte concentration of the target flow battery after the load change based on the change duration, the method further includes: Obtaining a single cell voltage of the target flow battery under variable load; Determining a correction amount of a change time of the variable load current based on the single cell voltage; The change duration is corrected based on the change duration correction amount.

3. The method for establishing electrolyte concentration of a flow battery according to claim 2, characterized in that: The correction amount for determining the change time length of the variable load current based on the single cell voltage includes: Subtracting the single cell voltage from a preset standard single cell voltage to obtain a target voltage difference; Determining whether it is necessary to correct the change duration of the variable load current based on the target voltage difference and a preset difference threshold; If the target voltage difference is less than the preset difference threshold, and the duration is greater than or equal to the preset duration threshold, the change duration correction amount is 0; If the target voltage difference is greater than or equal to the preset difference threshold, the change duration correction amount is determined based on the target voltage difference.

4. The method for establishing electrolyte concentration of a flow battery according to claim 3, characterized in that: Determining the change duration correction amount based on the target voltage difference includes: The adjustment amount of the variable load current is calculated based on the target voltage difference and the single cell internal resistance of the target liquid flow battery; The change duration correction amount is determined based on the adjustment amount of the variable load current.

5. The method for establishing electrolyte concentration of a flow battery according to claim 1, characterized in that: Obtaining the operating parameters of the target flow battery under variable load includes: The current capacity of the target liquid flow battery, the current temperature of the target liquid flow battery, the current circulation pump speed of the target liquid flow battery, and the variable load current of the target liquid flow battery are obtained.

6. The method for establishing electrolyte concentration of a flow battery according to claim 5, characterized in that: Querying a circulation pump speed characteristic diagram based on the operating parameters to determine the variable load required speed of the target flow battery includes: determining a corresponding flow resistance curve based on the current capacity or the current temperature; Determining the flow demand corresponding to the load after the load change based on the load change current; Based on the flow resistance curve and the flow demand, the variable load demand speed of the target liquid flow battery is determined using the circulation pump speed characteristic diagram.

7. The method for establishing electrolyte concentration of a flow battery according to claim 5, characterized in that: Determining the speed adjustment duration based on the variable load demand speed includes: Based on the current circulating pump speed and the variable load demand speed, a variable load rate curve diagram of the corresponding circulating pump is queried to determine the speed adjustment duration.

8. A device for establishing electrolyte concentration of a flow battery, characterized in that: The device comprises: A parameter acquisition unit, used to acquire the operating parameters of the target flow battery under variable load; A speed determination unit, configured to query a speed characteristic diagram of a circulating pump based on the operating parameters to determine a variable load required speed of the target liquid flow battery; A first time determination unit, configured to determine a speed adjustment duration based on the variable load demand speed; A second time determination unit, used to determine a change duration of the variable load current based on the speed adjustment duration; The concentration establishing constraint unit is used to constrain the establishment rate of the electrolyte concentration of the target liquid flow battery after the load is changed based on the change time length to ensure the output power to the load.

9. The electrolyte concentration establishing device for a flow battery according to claim 8, characterized in that: Before constraining the establishment rate of the electrolyte concentration of the target flow battery after the load change based on the change duration, the device further includes: A voltage acquisition unit, used to acquire the single cell voltage of the target flow battery under variable load; A correction amount determination unit, used to determine a correction amount of a change time length of the variable load current based on the single cell voltage; The duration correction unit is used to correct the changed duration based on the changed duration correction amount.

10. A liquid flow battery, characterized in that: The liquid flow battery implements the method for establishing electrolyte concentration of a liquid flow battery according to any one of claims 1 to 7.

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